Absorption spectroscopy is concerned with the range of electromagnetic spectra absorbed by a substance. In application Ser. No. 11/311,126, filed on Dec. 20, 2005, UV/VIS spectroscopy is used to obtain absorption information of a sample placed in a spectrophotometer. Ultraviolet and/or visible light at a certain wavelength (or range of wavelengths) is shined through the sample. The spectrophotometer measures how much of the light is absorbed by the sample.
Fluorometric spectroscopy concerns detection of fluorescent spectra emitted by a sample of interest. It involves using a beam of light, usually ultraviolet (UV) light, that excites the electrons in molecules of certain compounds in the sample and causes them to emit light of a lower energy. This lower energy light is typically, but not necessarily, visible light. This technique is popular in biochemical and medical applications, such as confocal microscopy, fluorescence resonance energy transfer and fluorescence lifetime imaging. Molecular fluorescence spectroscopy instrumentation generally consists of a source of excitation radiant energy, an excitation wavelength selector, a sample cell to contain the analyte material, an emission wavelength selector, a detector with signal processor and a readout device.
There are several types of fluorometers for measuring fluorescence. Filter fluorometers use optical filters to isolate the incident light and fluorescent light. Spectrofluorometers use diffraction grating monochromators to isolate the incident light and fluorescent light. In these devices, the spectrum consists of the intensity of emitted light as a function of the wavelength of either the incident light (excitation spectrum) or the emitted light, or both.
In cleaning and antimicrobial operations, commercial users, such as restaurants, hotels, food and beverage plants, grocery stores and the like, rely upon the concentration of the cleaning or antimicrobial product to make the product work effectively. Failure of a cleaning or antimicrobial product to work effectively (due to concentration issues) can cause a customer or consumer to perceive the cleaning and antimicrobial product as lower quality and the commercial users being perceived as organizations providing inferior services. In addition, they may be investigated and/or sanctioned by government regulatory and health agencies. Accordingly, there is a need for a system that can determine if the concentration of a product is within a specified concentration range. The same may be true for other applications, such as water care, pest control, beverage and bottling operations, packaging operations, and the like.